Page 12 of The Dark of the Moon
We pulled in through the gates, passing the guard house where Jess and I had presented ourselves the night before. The guard’s grim greeting – ‘Welcome to the lunatic asylum’ – rang in my ears, serving only to heighten my sense of uneasiness. But the other workers looked like a very ordinary and remarkably sane bunch of people, so I drew comfort from that. Most walked off towards some rather ugly-looking huts, but an officer with a clipboard herded those of us who were new around to the front of the main building. It was an extraordinary-looking edifice, a sprawling hotchpotch of an English country house comprised of a muddle of red brick and white stone. It seemed to have been designed with no particular eye for cohesion – Tudor timbering jostled for position between Gothic turrets and Baroque gables. An ornamental lake sat in front of the building, the water reflecting the grey of the January sky. A chill wind made me shiver and I folded my arms across the front of my ATA tunic, trying to protect myself from the cold as well as whatever it was that awaited us. The officer showed us in throughthe arched main door of the house, leading us to an entrance hall and telling us to take a seat.
When my name was called, I made my way down a long corridor to a room that had been commandeered as an office. An army captain sat behind a mahogany desk on which were placed some papers and a military pistol. He didn’t return my smile, just pointed to a chair, where I perched somewhat nervously, eyeing the gun. He pushed the papers across to me. ‘Read that and sign it,’ he said.
Printed across the top of the first sheet, beneath the royal coat of arms, were the words Official Secrets Act. By the time I’d finished reading it, I was fully aware of the fact that if I discussed or disclosed anything I saw or heard in my new workplace I’d be liable to receive a hefty jail sentence at the very least.
‘Do you understand?’ asked the captain, driving the point home. His tone was matter of fact. ‘Anything you read or hear around these parts is not to be discussed outside the department to which you’ll be assigned. Absolutely nothing is to be disclosed until thirty years after this war ends, not even to family members. An act of treason is an offence that carries the death penalty.’
I realised the pistol on the desk only served to reinforce the message. No wonder everyone on the bus had been silent.
‘I understand,’ I said. I signed my name at the bottom of the document.
The captain stood, saying, ‘Welcome to the Government Code and Cypher School, Miss Buchanan.’ He showed me out of the room, pointing me back down the hallway. I sat down on one of the chairs lining the wall and waited. Jess emerged from a different office, but I guessed she’d been signing those same papers. She raised her eyebrows and drew down the corners of her mouth in a comical expression of astonishment. I gave her a sympathetic smile,but we didn’t speak. At last, the officer with the clipboard returned and told us to follow him.
I was assigned to Hut 8. Judging by the smell of fresh paint, the huts had been built recently and hastily. They were of flimsy construction, tin-roofed and with walls and doors painted regulation MoD green. It was scarcely warmer inside than out and blackout blinds were pulled down, covering every window so there was no natural light. A friendly-looking girl in a Wren’s uniform got up from her chair when I entered the room, standing there rather awkwardly as I hadn’t a clue what was expected of me. ‘Hello,’ she said. ‘You must be the new cribber? Here, I’ll show you the ropes.’
Her name was Beryl, she told me. She’d been working at Bletchley Park for six months and was usually in the Machine Room, although she’d been standing in as a cribber for a few weeks as they were short-handed. Despite her cheery and helpful introduction, I was still none the wiser as to what a cribber was and what I was actually supposed to be doing. She handed me a typewritten manual, saying, ‘You can start off by reading the Prof’sTreatise on the Enigmawhen you have the time. It’ll tell you all you need to know about what we do here. But first, I’ll give you the guided tour.’
She showed me round, eventually opening a door leading off from the corridor. It was as spartan as the other rooms in the hut, with a couple of desks set on a slant in the centre and a large filing cabinet pushed into one corner. ‘This is the new crib girl,’ she said to the two men who stood beside the cast-iron radiator, tin mugs of tea in their hands.
‘Hugh Alexander, pleased to meet you. Welcome to Hut 8, Miss Buchanan. This is Alan.’
And so it was that I met my new boss, Alan Turing – also known as the Prof – and became one of the Bletchley Park codebreakers.
By the time I joined Hut 8, the codebreakers had already developed a machine that could be used to help break the Enigma code, which the German military used for their most critical messages. Secret radio stations across Europe would intercept the messages, transmitted in Morse code, and relay them to the Registration Room at Bletchley Park. There, they were logged and then passed on to the codebreaking teams. The machines Beryl had referred to – known as bombes – were only effective up to a certain point in decrypting these complicated codes. Before the bombes could be configured to try to discover that day’s Enigma settings, sheets known as menus had to be drawn up.
And that’s where the cribbers came in. We had to narrow down the possible permutations, then draw up the menus showing probable combinations, which would be passed to the Wrens to set up the machines. The messages would be run through the bombes, their drums spinning and clattering, until a likely setting was discovered. Then the machine would fall silent, its rotors stopping, and the result passed to Mr Turing and his team of cryptanalysts. Once the correct settings were ascertained, they’d be sent over to the Decoding Room, where the day’s Enigma intercepts could be run through Typex machines to decode them back into German, which could then be translated. The final messages, in English, were then sent up to the British High Command in London, keeping Mr Churchill apprised of Adolf Hitler’s every move. I learned most of this from Beryl, who was friendly and talkative within the safe confines of our hut.
I soon settled in and kept my head down, focusing on the job as I tried to work out any discernible patterns within the columns of figures on the table before me. There was little to go on, butslowly I began to spot clues here and there. If the message was a weather report or some daily news from the front, for example, it could be possible to tease out certain commonly used words or phrases. I derived a good deal of satisfaction from compiling the day’s menu and passing it over to the Machine Room, knowing we were one step closer to breaking that day’s cipher.
The work was relentless. Every day the Germans changed the settings they were using to transmit messages and every day we had to re-decipher the codes to try to keep up. We worked around the clock in shifts, eight until four, four to midnight, midnight to eight.
After a few weeks, I was set to work the graveyard shift, from midnight to eight, literally left ‘minding the Baby’. The ‘Baby’ in question was a specially designed machine that could be used to reverse engineer a cipher. It was another of the shortcuts we’d devised to try to speed up the process. We’d worked out that the Germans always spelled out numbers in full when transmitting them. So we took the number one –eins– and used the Baby to work out all the different ways this frequently used four-letter word could be coded. It narrowed things down, even though there were still more than 17,000 ways that one word could be encoded. My job was to make regular checks and reset the Baby to start another run when a cycle was completed. The results were typed out into a table we called theEinscatalogue.
It was quiet in the hut that night, and I was struggling to stay awake when I heard the door open and then soft footsteps in the corridor. I jumped up and went to see who it was.
‘Oh, hello, Alan.’
‘Sorry, Philly, I hope I didn’t startle you. I couldn’t sleep – was mulling over a problem I’d been working on earlier. Thought I might as well come in and carry on.’
The Prof’s hair was uncombed, his face pale and drawn beneath the stark overhead light. There were dark smudges under his eyes, betraying the strain placed on him by the pressures of his work.
‘I’ll make us a cup of tea, shall I, before you start?’
He smiled, setting down his attaché case and hanging his coat on the stand in the corner. ‘Thanks. That would be great.’
I carried two steaming tin cups through, setting one on the corner of his desk, careful not to disturb the muddle of papers spread out in front of him. He must have seen my interested glance at the problem he was working on because he pushed it across so I could cast an eye over it. More out of generosity of spirit than any actual need for my help with it, I suspected. Although his manner was always quite shy and awkward, I knew what a brilliant mind he had, and I learned a lot from watching him work whenever I had the opportunity.
His intellect was dazzling, and as I followed his workings I saw how he could leap to a solution, seemingly instinctively. I was more of a plodder, preferring to work things through methodically, being thorough and checking my working at every stage. I reached for a blank sheet of paper and a pencil, writing down the steps he’d followed to get them clear in my head.
When I glanced up, he was watching me closely. ‘You remind me of the Polish mathematicians I met in France,’ he said. ‘They used the same approach.’
‘Well, I am half Polish,’ I replied with a smile, ‘so maybe it’s a cultural thing. Who were these mathematicians you met?’
‘There were three of them. Fortunately for us, they’d been working on decoding Enigma for some years before the war broke out. They’d made huge progress. When Germany invaded Poland, they were whisked away to Paris by the French intelligence service, who saw how useful their work could be. It was the French who set up the meeting between us. Dilly and I went over for it. Andif it weren’t for what they so generously handed over to me at that meeting, we wouldn’t have been able to develop the bombe so quickly. They’d already made a basic prototype, you see, called it abomba, which is where we got the name. Without their help, we wouldn’t be anywhere near where we are today in terms of breaking Enigma.’
‘Where are the Polish mathematicians now?’ I asked. ‘Did you bring them to England?’
He laughed, a little hollowly. ‘No, the powers that be decided it was better to leave them where they were. The top brass here dithered about bringing them over and so the French, who knew what an asset they had, kept ahold of them. As far as I know, they’re hiding away somewhere in Vichy France, which is probably about as safe as they can get when the rest of the country’s now occupied by the Nazis.’
